1235315

Appears in sequences

• (3*7^n+1)/2.at n=7A199417
• T(n,k)=Number of nXk 0..3 arrays with no element x(i,j) adjacent to value 3-x(i,j) horizontally or vertically, top left element zero, and 1 appearing before 2 in row major order.at n=37A233018
• a(n) is the smallest positive integer of length (distance from origin) n in the Cayley graph of the integers generated by all powers of 7.at n=22A297180